Middle Pleistocene of Western Europe

Abstract

This article is concerned with middle Pleistocene beetle assemblages from a limited region of Western Europe because these faunas are now well known and can be placed in a sound stratigraphical and chronological context. Insect assemblages have been described from organic deposits at many sites in the British Isles mostly in southern and central England and only a few insect faunas have been investigated in recent years from the rest of Europe. All these faunas are made up of species that are still living today: there is no evidence of any evolution or global extinction. However, many species have changed their geographical distributions on an enormous scale so that their modern occurrences may be far from the places where they are now found as fossils. On the assumption that this morphological stability is accompanied by a similar degree of physiological constancy, the occurrences of species in a fossil assemblage are used to interpret past local environments and in particular regional climatic changes. These interpretations have involved the use of assemblages of several hundred beetle species with very varied ecological requirements that include, for example, carnivores and phytophages, terrestrial, and aquatic species as well as numerous specialist groups such as dung and carcase beetles and species that are wholly dependent on trees, either dead or alive. The coleopteran faunas thus reflect a broad ecological response to the fluctuations in the physical environment.